1 cup skinned hazelnuts
2 tbsp very strong brewed coffee
1 1/2 cups self-rising flour
9 ounces milk or dark chocolate rolled wafer cookies
1 tsp baking powder
20 chocolate-covered coffee beans
1 cup unsalted butter, softened, plus more for the pan
2/3 cup packed brown sugar
1 1/3 cups unsalted butter, softened (for buttercream)
4 cups confectioners' sugar (for buttercream)
4 large eggs, lightly beaten
2 teaspoons vanilla extract (for buttercream)
2 tbsp milk
Preheat the oven to 350F.
To make the Coffee and Hazelnut Cake Batter: Sift together the flour and baking powder into a bowl and set aside.
In an electric mixer, or in a large bowl with a hand mixer, cream together the butter and sugar for about 5 minutes until very light and fluffy.
Add the eggs very slowly, with the mixer running, adding 1 tablespoon of the flour during the process to prevent curdling.
Finally, using a large rubber spatula, fold in the remaining flour, the finely chopped hazelnuts, milk, and coffee until well blended.
To make the Giant Cupcake: Lightly butter two 6 x 3" cake pans and line the bottoms with parchment paper. Pour the batter into the pans and smooth. Bake for 30-35 minutes. Let cool completely. Freeze for about an hour (this makes it much easier to shape).
To make Buttercream: In an electric mixer, beat the butter until really pale and fluffy. Add your vanilla and sugar and beat for at least 5 minutes, until light and creamy.
Take 1 cake and, with a very sharp knife, cut down the sides at an angle so that it is narrower at the base (to mimic a cupcake liner). Slice the cake horizontally and fill with buttercream, spreading it on the top surface, too.
Take the second cake and place on top. Cut it into a dome, then slice it in half horizontally and fill with buttercream.
Spread a layer of buttercream around the sides of the bottom cake and put the remainder into the pastry bag fitted with the star tip. Ice the top with swirls of buttercream, just as you would a small cupcake.
Arrange the chocolate cookies vertically all around the sides of the cake for the "cupcake case," pressing them into the buttercream. Sprinkle the chocolate coffee beans over the cake and place the candle on top.